A terminal block of this type is already known for example from DE 37 28 368 C1. For latching the terminal block onto round profiled bars, the terminal block has on the underside of its insulating part arcuate connecting elements which enclose the profiled bars by an angle of over 180°. The inside diameter of the arcuate connecting elements corresponds to the outside diameter of the round profiled bars. On account of the terminal blocks, and in particular the lower part, being formed from plastic, the side walls of the connecting elements are flexible, so that they can be pressed over the round profiled bar and latched onto it. The arcuate connecting elements bear on the outer side rectangular wire-guiding saddles, which are slotted in the center. Extending through the arcuate connecting elements, parallel to the outer walls of the upper part, are through-slots, into which there can be inserted metallic ground-contact saddles, which are clamped onto the round profiled bars at ground potential and onto which contact terminals of a surge arrester mounting unit, which can be inserted into the terminal block, can be clamped from above. The ground-contact saddles have in the lower region three arcuate saddles, the inner contour of which is made to match the round profiled bar. Formed onto one saddle of the ground-contact saddle is a contacting prong, which engages in an upwardly open chamber of the terminal block. The lower part of the terminal block also has on the outer side of the arcuate connecting elements insertion slots which are used for prizing the terminal block out of the position in which it is latched with a round profiled bar using a screwdriver.
A terminal block with two terminal strips angled away from one another and a shielding device is known from DE 100 01 553 A1. Each terminal strip comprises 24 insulation-displacement contact elements, the respectively opposing insulation-displacement contact elements of the two terminal strips being electrically connected to one another. The insulation-displacement contact elements are arranged in an insulator, on the underside of which half-shell-shaped fastening elements are arranged, by means of which the terminal block can be pushed or latched onto a profiled bar. Groups of three neighboring insulation-displacement contact elements serve for the wiring of a twin conductor with shielding. The upper terminal strip in this case forms the switching side, and the terminal strip aligned vertically in relation to said upper terminal strip forms the cable-conductor side. The shielding device comprises a shielding plate, a web arranged perpendicularly in relation to the shielding plate and a row of contact fingers. On the shielding plate, T-shaped webs are provided on its underside and further T-shaped [lacuna] are provided centrally. Furthermore, the shielding plate has two screw-contact elements. The web projects perpendicularly from the upper side of the shielding plate, the row of contact fingers again being formed perpendicularly in relation to the web. As a result, the contact fingers form a plane parallel to the shielding plate. The shielding plate, the web and the row of contact fingers are in this case preferably formed in one piece. For connecting a cable with eight twin conductors and shielding, the cable is initially fastened to the T-shaped webs by means of cable ties. The shielding is twisted and is mechanically and electrically connected to the shielding plate by means of one of the screw-contact elements. Then, in the mounted state, the shielding plate is electrically connected to the profiled bars by means of a connection not described in any more detail and is grounded by means of said profiled bars. The insulation-displacement contact elements assigned to the shielding are connected by means of the contact fingers to the shielding plate and consequently to ground.
A terminal block for latching onto a mounting bracket is known from DE 196 52 422 C1, a connecting element corresponding to the mounting bracket being arranged on the underside. The connecting element in each case comprises two essentially parallel side walls, on which latching projections are arranged, so that, during latching onto the mounting bracket, said latching projections press against said mounting bracket and latch the terminal block. A ground connection between the terminal block and the mounting bracket via this connecting element is not envisaged.
On account of the increasing requirements with regard to transmission speed, terminal blocks with shielding contacting, as described for example in DE 100 01 553 A1, are being used increasingly. On the other hand, the terminal blocks are to be as flexible as possible in their use for the different types of mounting locations, such as for example round profiled bars or mounting brackets, so that a ground connection to mounting brackets is also made possible.